Indicator-actuating mechanism.



O. E. KELLUM.

INDICATOR AOTUATING MECHANISM.

APPLICATION FILED NOV. 23, 1910.

Patented Apr. 9, 1912.

"0/142 F u w V lat. f z r UNITED STATES OFFICE. I

OBLANDO E. KELLUM, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO NATIONAL STREET AND STATION INDICATOR COMPANY, OF'LOS ANGELES, CALIFORNIA, A CORPORA- TION OF CALIFORNIA.

INDICATOB-ACTUATIN G MECHANISM.

Specification of Letters Patent.

Application filed November 23, 1910. Serial No. 593,831.

To all whom it may concern:

.Be it known that I, ORLANDO E. KELLUM, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Indicator-Actuating Mechanisms, of which the followin is a specification.

his invention relates to an electrically operated magnetic mechanism for producing a step by step movement for an indicator, such as a station indicator for rail- A stroke is reached.

ways; and it consists in an electro-magnetic mechanism adapted for producing an easy starting and stopping movement and of accurate extent. The general difiiculty with electro-magnetic mechanisms has been that they were, in themselves, almost instantaneous in action and were liable to strain and shock the indicator mechanisms operated by them; and that to overcome this difliculty certain restraining devices were necessarily em loyed; and with all these devices the liability of over or under travel was very great.

The present invention consists of an electrically excited magnetic pole or poles with an armature adapted to swing in proximity. The armature is normally set in its initial position by a spring, being attracted through a certain angle by the magnet. The arrangement is such that the pulling power increases toward the center of the stroke and then gradually decreases to the end, all shocks being thus avoided. The armature is set loosely on a shaft, being preferably the shaft which extends directly to the indicator mechanism or other device which is desired to be operated step by step. A ratchet wheel is tightly mounted on the shaft and is adapted to-be moved by pawls mounted on the armature. Reversal of movement is accomplished by moving a stop mechanism which holds the armature normally in a position with either end tilted toward the pole piece; and the pawls are two in number with one held out of engagement with the ratchet wheel by riding over the face of a cam. The mechanism is stopped accurately in position by a set of pawls, also operated by a cam, which engage with ratchet teeth when the end of the In the accompanying drawings I have shown the preferred form of my device, in which drawings:

Figure 1 is a front elevation of my mechanism. Fig. 2 is a side elevation of the same. Fig. 3 is a section taken on line 33 of Fig. 1.

In the drawings 5 designates a magnetic frame provided with electric windings 6 and concaved pole pieces 7. A bearing plate 8 is mounted across the faces of the pole pieces and is provided with a central aperture 9 which indirectly becomes the bearing for shaft 10. Shaft 10 carries a ratchet wheel 11 preferably provided with six ratchet teeth capable of being engaged from either direction.

Loosely mounted on shaft 10 is an armature 12 adapted to rotate between the concaved pole pieces of the magnetic frame. A stop frame 13 is slidably mounted over the to of the magnetic frame and is, adapted to e thrown from a position on one side to the other, being shown in position on the left hand side of Fig. 1. This stop frame is provided with two engaging parts 14 which limit the spring actuated movement of the armature 12, coiled spring 15 being utilized to throw the armature toward a vertical position. With the armature held in the position shown, when the magnetic frame is polarized, the armature will rotate in a left hand direction in Fig. 1, while if the stop frame 13 be moved to the other side, the armature would be held in a position on the other side of the vertical and would be rotated in a right hand direction -when the current is supplied to the pole windings. The stop frame is moved by any convenient mechanism such as is shown at 20, a handle 21 being provided for manipulation. It will be seen that the relative position of the armature and pole pieces accomplish one of the ob'ects before mentioned, namely the starting torque of the armature being comparatively small, owing to its distance from the centers of force in the pole pieces, and also that at the end of the stroke the torque'decreases again owing to the fact that the armature is then taking a position extending directly across the s ace between the pole pieces, in which position'there can be no torque exerted upon it.

Armature 12 carries two pawls 25 pivotally mounted and pressed by a spring 26 Patented Apr. 9, 1912.

toward and into engagement with ratchet 11. A- stationary 'cam 27 is mounted on hearing plate 8 and pawls 25 are adapted to ride over this cam and to be held out of engagement with the ratchet teeth. Cam 27 extends sufficiently to hold one of the pawls always out of engagement with the teeth, which pawl this shall be depending upon the position of the armature. In the position illustrated in Fig. 1 it will be seen that the left hand ratchet is allowed to engage with one of the ratchet teeth ready to move ratchet wheel 11 and shaft 10 in the direction indicated by the arrow when the armature moves in that direction. Right hand pawl 25 will be seen to merely ride over the cam face without touching the ratchet teeth. Then the position of the armature is reversed, the right hand pawl will engage with the ratchet teeth and the left hand pawl will ride over the cam face.

Mounted on shaft 10 and moving with armature 12 is a cam 30 having a raised face which projects beyond the ratchet teeth. A pair of pawls 31 are pivotally mounted on bearing plate 8 and are spring pressed upwardly into engagement with cam 30 or with the ratchet teeth. The extent of cam 30 is such that one of pawls 31 (the left hand one, as the mechanism is illustrated in Fig. 1) is let into engagement with the ratchet wheel in front of the tooth being impelled by pawl 25 and so as-to engage that tooth at the end of the proper stroke, being in this case a sixth of a revolution. The end 32 of cam 30 comes behind the ratchet tooth which will be opposite the engaging end of right hand pawl 31, so that right hand pawl 31 is allowed to drop over the tooth just as the ratchet reaches the end of its stroke and just as left hand pawl 31 engages with a ratchet tooth to stop the movement. By this action of the righthand pawl the ratchet wheel is prevented from rebounding when stopped by the left hand pawl; but the right hand pawl is immediately lifted by the return motion of cam 30 with the armature. The whole mechanism is thus stopped in position, and the current having been interrupted, the armature is allowed to move back under the influence of spring 15. Cam 30 again raises pawl 31 and pawl 25 rides over the next tooth and engages behind it ready for the next operation of the machine.

It will be seen that, when the armature is held in its central vertical position by appropriate movement of the stop frame, both of pawls 25 will be held out of engagement with the ratchet and the shaft 10 may then be turned by hand in either direction. In this purpose a pin 10" is provided for engagement by a hand wheel or other device, means being thus provided for manually adjusting the position of-the mechanism operated by the present device.

It will be understood that the present invention resides directly in the broad features of the mechanism above described. Any sort of machine may be operated b tion, and a switch mechanism 0 any desired character may be used to supply my machine with current for its periods of operation. This would include any sort of direct switch or a relay system for prolonging the duration of current passage until the full operation of my invention be accomplished.

Having described my invention, I claim:

1. A mechanism of the class described, comprising an electro-magnetically charged pole piece, an armature rotatably mounted adjacent the pole piece and adapted to be attracted thereby, a ratchet wheel, pawls on the armature for engaging with the ratchet wheel, a stationary cam over which the pawls are adapted to ride and be held out of engagement with the ratchet wheel during a portion of their movement, stop means or holding the armature inclined to or from the pole piece, pawls adapted to engage with the ratchet wheel to stop the movement thereof,

and a cam mounted on the armature and engaging with the last named pawls to disengage them from the ratchet wheel.

2. A mechanism of the class described, comprising an electro-magnetically char ed pole piece, an oscillating armature, a rate et wheel mounted concentrically with the oscillat-ing armature, a pawl on the oscillating armature and adapted to engage the teeth of the ratchet wheel, stationary pawls adapted to engage the teeth of the ratchet wheel to stop the same, and a cam oscillating with the armature and adapted to raise the stationary pawls out of engagement with the ratchet wheel.

3. A mechanism of the class described, comprising an electro-magnetically charged pole piece, an oscillating armature, means to hold the armature tilted toward or from the pole piece, a ratchet wheel mounted concentrically with the oscillating armature, a pawl on the armature and adapted to engage the teeth of the ratchet wheel, a stationary pawl adapted to engage the teeth of the ratchet wheel to stop the same, and a cam oscillating with the oscillating armature and adapted to raise the stationary pawl out of engagement with the ratchet wheel.

4. A mechanism of the class described, comprising an electro-magnetically charged pole piece, an oscillating armature, means to hold the armature inclined to or from the pole piece, a ratchet wheel concentrically mounted with the oscillating armature, a pair of pawls mounted on the armature and adapted to engage the teeth of the ratchet wheel for movement of the ratchet wheel in opposite directions, a stationary cam over which the pawls are adapted to slide and be held out of engagement with the ratchet my invenwheel during a portion of their movement, a In witness that I claim the foregoin I- pair of statlonary pawls adapted to engage have hereunto subscribed my name this 1 th with the teeth of the ratchet wheel to stop day of November 1910.

the movement thereof, and a cam oscillating ORLANDO E. KELLUM. 5 with the armature and engaging with the Witnesses: stationary pawls to disengage them from the JAMES T. BARKELEW,

teeth of the ratchet wheel. Enwoon H. BARKELEW. 

